JP2007278093A - Fuel injection valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel injection valve in which drop of pressure-resistance performace is controlled. <P>SOLUTION: The fuel injection valve 1 includes a nozzle 13 for injecting fuel, a nozzle body 10 having a needle-holding hole 11 for holding a needle 16 controlling injection from the nozzle 13, and a plate 30 which is provided adjacently to the nozzle body 10, and has a fuel path 33 for supplying the fuel to the needle-holding hole 11. On the end face 34 on the nozzle-body side of the plate 30, an annular groove 35 connecting the fuel path 33 to the needle-holding hole 11 is formed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fuel injection valve.

  2. Description of the Related Art Conventionally, a nozzle body having an injection hole for injecting fuel and a needle accommodation hole for accommodating a needle for controlling injection from the injection hole, and a fuel passage provided adjacent to the nozzle body and supplying fuel to the needle accommodation hole There is known a fuel injection valve provided with a plate having (see Patent Documents 1 to 3).

The fuel passage of the fuel injection valve of the type disclosed in Patent Documents 1 to 3 needs to supply fuel to the outer peripheral side of the needle accommodated along the axis of the needle accommodation hole. The plate is formed so as to be shifted from the needle accommodation hole. And the notch which connects a needle accommodation hole and a fuel passage is formed in the needle accommodation hole.
German Patent Application Publication No. 10023952 German Patent Application Publication No. 10024703 German Patent Application Publication No. 100002997

  However, since the fuel injection valve has a notch, when the injection pressure is increased, stress is concentrated on this portion, resulting in a problem that the pressure resistance performance of the nozzle body is lowered. On the other hand, it is conceivable to increase the inner diameter of the needle accommodation hole in order to eliminate the notch. However, if the outer diameter of the nozzle body is kept as it is, the thickness of the nozzle body is reduced and the pressure resistance performance is lowered. .

  The present invention has been made in view of the above points, and an object thereof is to provide a fuel injection valve capable of suppressing a decrease in pressure resistance.

  According to the first aspect of the present invention, a nozzle body having an injection hole for injecting fuel, a needle accommodation hole for accommodating a needle for controlling injection from the injection hole, and a needle accommodation hole provided adjacent to the nozzle body. And a plate having a fuel passage for supplying fuel to the end of the plate on the nozzle body side, wherein an annular groove for connecting the fuel passage and the needle accommodation hole is formed. Yes.

  According to this invention, since the annular groove for connecting the fuel passage and the needle accommodation hole is provided on the nozzle body side end surface of the plate, the fuel passage formed in the plate is arranged to be offset with respect to the accommodation hole. Even with a simple structure, a fuel flow path from the fuel passage to the needle accommodation hole can be secured. As a result, it is not necessary to provide a notch or enlarge the inner diameter of the accommodation hole as in the prior art fuel injection valve, so that a decrease in pressure resistance can be suppressed.

  According to the second aspect of the present invention, the needle receiving hole is provided with a cylinder having a hollow portion in which the needle slides adjacent to the plate, and the cylinder is provided with the needle receiving hole. The outer circumferential wall and the inner wall of the needle receiving hole facing it are separated from each other into the annular passage that communicates with the annular groove and the high-pressure chamber that communicates with the injection hole at the boundary. The width and depth satisfy the condition that the sum of the circumferential cross-sectional area of the annular passage and the circumferential cross-sectional area of the annular groove is ½ or more of the passage cross-sectional area of the fuel passage. .

  According to this invention, the width and depth of the annular groove are such that the sum of the circumferential cross-sectional area of the annular passage and the circumferential cross-sectional area of the annular groove is not less than 1/2 of the passage sectional area of the fuel passage. Therefore, the fuel flowing through the fuel passage can be spread all over the annular groove and the annular passage, and a large amount of fuel is supplied to the outer peripheral wall of the cylinder and the needle housing hole facing the cylinder. The high-pressure chamber can be supplied through a portion where the inner wall distance is the narrowest.

  According to a third aspect of the present invention, the nozzle body has a pin groove or pin hole for locking a pin for determining a circumferential position between the nozzle body and the plate, the pin groove or pin hole, The groove is characterized by being displaced in the radial direction.

  The thickness of the pin groove or pin hole formed in the nozzle body is smaller than that of other portions. For this reason, when high-pressure fuel enters the pin groove or the pin hole, the pressure resistance performance of the nozzle body may be reduced.

  On the other hand, according to the present invention, the pin groove or the pin hole and the annular groove formed on the nozzle body side end surface of the plate are displaced in the radial direction. Since the surface where the nozzle body side end surface of the nozzle body contacts the plate side end surface of the nozzle body is formed, fuel leaking from the annular groove into the pin groove or the pin hole can be prevented. For this reason, the pressure-resistant performance of the nozzle body due to high-pressure fuel entering the pin groove or the pin hole can be prevented from decreasing.

  According to a fourth aspect of the present invention, the width of the annular groove is not less than the passage diameter of the fuel passage. According to this invention, since the width of the annular groove is equal to or larger than the passage diameter of the fuel passage, the processing of the annular groove is facilitated.

  According to the fifth aspect of the present invention, a meat stealing portion is formed on the end surface of the plate on the nozzle body side, and the meat stealing portion and the annular groove are shifted in the radial direction.

  According to this invention, even if the fuel in the annular groove flows out from the annular groove through the both ends of the plate and the nozzle body, the fuel can be temporarily stored in the meat stealing portion, and the fuel injection valve Can prevent fuel leakage to the outside.

  According to the invention described in claim 6, the outer peripheral edge of the annular groove is located outside the inner wall of the needle accommodation hole.

  According to this invention, since the outer peripheral edge of the annular groove is located outside the inner wall of the needle housing hole, the inner diameter of the needle housing hole of the nozzle body can be made as small as possible, and the thickness of the nozzle body can be reduced. It can be secured.

  According to the seventh aspect of the present invention, a nozzle body having an injection hole for injecting fuel and a needle storage hole for storing a needle for controlling injection from the injection hole, and provided adjacent to the nozzle body, the needle storage hole In the fuel injection valve having a plate having a fuel passage for supplying fuel to the nozzle, a groove portion for connecting the fuel passage and the needle accommodation hole is formed on the end surface of the plate on the nozzle body side. It is a groove having a width or a circumferential length in which the area of the portion where the hole and the opening of the groove overlap is greater than or equal to the cross-sectional area of the fuel passage.

  According to the present invention, the area of the portion where the opening of the groove portion formed in the plate and the needle accommodation hole overlap is equal to or larger than the passage cross-sectional area of the fuel passage, so that per unit time of the fuel flowing through the fuel passage The fuel can be supplied to the needle accommodation hole without reducing the flow rate of the nozzle.

  The best mode for carrying out the present invention will be described in detail with reference to the following embodiments.

(One embodiment)
FIG. 1 is a cross-sectional view of a main part of a fuel injection valve 1 according to an embodiment of the present invention. A fuel injection valve 1 shown in FIG. 1 is used, for example, in an accumulator fuel injection system for a diesel engine, and injects high-pressure fuel supplied from a common rail (not shown) into a cylinder of the diesel engine. The nozzle part, back pressure control part, and piezo drive part which are described in (1) are provided.

  The nozzle portion includes a nozzle body 10, a needle 16 slidably held on the nozzle body 10, a cylinder 19 in which the needle 16 is inserted, and a nozzle spring 20 that urges the needle 16 in the closing direction.

  The nozzle body 10 is a bottomed cylindrical housing having a needle accommodation hole 11 that accommodates a needle 16, a cylinder 19, and a nozzle spring 20 in a substantially central portion. A nozzle hole 13 through which high pressure fuel is injected into a cylinder of a diesel engine is formed at the bottom of the nozzle body 10, and a mortar-shaped valve seat 12 is formed at the upstream side of the nozzle hole 13.

  The needle 16 is a substantially cylindrical valve body having a conical seat portion 18 at the tip, which controls whether or not high pressure fuel is ejected from the nozzle hole 13. The needle 16 is provided so as to be able to reciprocate, and the injection of high-pressure fuel from the injection hole 13 can be controlled by seating the seat portion 18 on the valve seat 12. A flange 17 that receives the urging force of the nozzle spring 20 is formed in the middle of the needle 16.

  The cylinder 19 is a substantially cylindrical part, and is accommodated in the needle accommodation hole 11 in the same manner as the needle 16. The inner peripheral wall 19e of the cylinder 19 can slidably support the upper portion of the needle 16. A gap is formed between the outer peripheral wall 19 c of the cylinder 19 and the inner wall of the needle accommodation hole 11. A lower end surface 19 b of the cylinder 19 is a surface facing the flange 17 and supports the other end of the nozzle spring 20. On the upper end surface 19a side of the outer peripheral wall 19c of the cylinder 19, an inclined surface 19d is formed such that the outer diameter decreases as the upper end surface 19a is approached.

  Above the nozzle body 10, a cylindrical plate 30 is provided adjacently so that the plate-side end face 15 of the nozzle body 10 and the body-side end face 34 of the plate 30 are in close contact with each other. When the needle 16 is inserted into the cylinder 19 and accommodated in the needle accommodation hole 11, the needle accommodation hole 11 is divided into three spaces: a back pressure chamber 22, a high pressure chamber 21, and an annular passage 23.

  As shown in FIG. 1, the back pressure chamber 22 is a space defined by the upper end surface of the needle 16, the inner peripheral wall 19e of the cylinder 19, and the body side end surface 34 of the plate 30, and has a predetermined pressure in this space. The force that presses the needle 16 against the nozzle hole 13 side is changed by introducing the fuel thus changed and changing the pressure.

  The annular passage 23 is a space defined by the inner wall of the needle accommodation hole 11 and the inclined surface 19d of the cylinder 19, and is supplied with high-pressure fuel in the common rail at least during operation of the diesel engine.

  The high pressure chamber 21 is a space defined by the inner wall of the needle accommodation hole 11 and the lower end surface 19 b of the cylinder 19. The high pressure chamber 21 communicates with the annular passage 23 via the injection hole 13 and the fourth high pressure fuel passage 24 formed by the outer peripheral wall 19c of the cylinder 19 and the inner wall of the needle housing hole 11 facing the outer peripheral wall 19c. ing. For this reason, the high-pressure chamber 21 is supplied with the high-pressure fuel in the common rail through the fourth high-pressure fuel passage 24 at least during the operation of the diesel engine, and when the seat portion 18 of the needle 16 is separated from the valve seat 12, High-pressure fuel is injected from the injection hole 13. The fourth high-pressure fuel passage 24 corresponds to a “portion in which the distance between the outer peripheral wall of the cylinder and the inner wall of the needle accommodation hole facing it is the narrowest”.

  The back pressure control unit controls the pressure in the back pressure chamber 22, and includes a plate 30, a valve plate 40, a valve body 45, and a spring 46. The plate 30 and the valve plate 40 are formed with a valve chamber 41 for accommodating various fuel passages and valve bodies 45 for controlling the pressure of the back pressure chamber 22 and supplying fuel to the annular passage 23 and the high pressure chamber 21. Has been. The plate 30 is provided adjacent to the nozzle body 10, and the valve plate 40 is provided adjacent to the plate 30.

  The plate 30 is a substantially cylindrical part, and a third high-pressure fuel passage 33, a first communication passage 31, and a second communication passage 32 are formed therein. The third high-pressure fuel passage 33 is a passage for supplying high-pressure fuel in the common rail to the annular passage 23, and is formed along the axial direction of the fuel injection valve 1. The first communication passage 31 is a passage for supplying high-pressure fuel to a valve chamber 41 formed in the valve plate 40, and the second communication passage 32 is a passage for communicating the valve chamber 41 and the back pressure chamber 22. . The third high-pressure fuel passage 33 corresponds to the fuel passage according to claim 1.

  In the valve plate 40, the high pressure fuel in the common rail is supplied to the valve chamber 41 that can accommodate the valve body 45, the low pressure fuel passage 43 for discharging the fuel in the valve chamber 41 to the low pressure side, and the third high pressure fuel passage 33. A second high-pressure fuel passage 42 to be supplied is formed. Connected to the valve chamber 41 are a first communication passage 31, a second communication passage 32, a valve needle accommodation hole 44, and a low-pressure fuel passage 43. The valve body 45 has a function as a so-called three-way valve. The valve body 45 has a first position in which the high-pressure fuel in the first communication passage 31 is supplied to the back pressure chamber 22 through the second communication passage 32. This is a control valve that reciprocates a second position for discharging the fuel in the pressure chamber 22 to the low pressure fuel passage 43. The valve chamber 41 is provided with a spring 46 that biases the valve body 45 in the direction of the first position.

  The valve body 45 is in contact with a valve needle 55 that is accommodated in the valve needle accommodation hole 44 and transmits the driving force of the piezo drive unit to the valve body 45. When the valve needle 55 reciprocates, the valve body 45 is controlled to the first and second positions.

  The piezo drive unit includes a low pressure chamber 51 filled with low pressure fuel inside a valve body 50 provided adjacent to the valve plate 40, and a first high pressure fuel passage for supplying high pressure fuel in the common rail to the second high pressure fuel passage 42. 52, a piezo stack (not shown) accommodated in the upper portion of the low pressure chamber 51, and a driving force transmission unit accommodated in the lower side of the piezo stack.

  The low-pressure chamber 51 is partitioned by forming a vertical hole with a circular cross section inside the valve body 50, disposing the valve plate 40 on the lower end surface of the valve body 50 where the vertical hole opens and closing the opening of the vertical hole. . The low pressure chamber 51 communicates with the valve chamber 41 through the valve needle accommodation hole 44. The low pressure chamber 51 communicates with the valve chamber 41 through the low pressure fuel passage 43 separately from the housing hole 44. Further, the low pressure chamber 51 is connected to a pipe that leads to a fuel tank (not shown).

  The piezo stack has a general capacitor structure in which piezoelectric ceramic layers such as PZT and electrode layers are alternately stacked, and is charged and discharged via a drive circuit (not shown). By being charged and discharged, it expands and contracts in the vertical direction of FIG.

  The driving force transmission unit transmits the displacement of the piezo stack to the valve needle 55. The piston cylinder 56 provided in the low pressure chamber 51, the first piston 53, the second piston 54 inserted into the cylinder 56, both The oil-tight chamber 59 formed between the pistons 53 and 54, and the oil-tight chamber 59, one of which is supported by the first piston 53 and the other is supported by the piston cylinder 59, the first piston 53 and the piston cylinder 59, The first piston spring 57 generates a biasing force that pushes the pistons 53 in opposite directions, and the second piston spring 58 generates a biasing force that pushes the pistons 53 and 54 in opposite directions.

  The first piston 53 is disposed on the lower side of the piezo stack, and is pressed against the lower end portion of the piezo stack by a first piston spring 57. It reciprocates in the piston cylinder 56 according to the displacement of the piezo stack.

  The second piston 54 is disposed below the first piston 53 via the oil tight chamber 59. The second piston 54 reciprocates in the piston cylinder 56 according to the displacement of the first piston 53. Since the valve needle 55 is disposed below the second piston 54, the valve needle 55 reciprocates in accordance with the displacement of the second piston 54. The reciprocating movement of the valve needle 55 is transmitted to the valve body 45. As a result, the valve body 45 reciprocates in the valve chamber 41 and is controlled to the first and second positions.

  The nozzle body 10, the plate 30, the valve plate 40, and the valve body 50 are formed with a pin hole 37 and a pin groove 14 for locking a pin 60 for aligning the circumferential position of each component. After the components are combined in the axial direction, the circumferential position of each component is fixed by locking the pin 60 in the pin hole 37 or the pin groove 14. Furthermore, each component is firmly fixed by the retaining nut 70. In the present embodiment, the pin groove 14 is formed only in the nozzle body 10, but this may be a hole shape like the plate 30 or the like.

  Next, the operation of the fuel injection valve 1 having the above configuration will be described.

  When the piezo stack is energized via the drive circuit and the piezo stack expands, the displacement is transmitted from the first piston 53 to the second piston 54 via the fuel in the oil-tight chamber 59 and further to the valve needle 55. The valve needle 55 moves in the valve needle housing hole 44 to the anti-low pressure chamber 51 side (lower side in FIG. 1), and moves the valve body 45 from the first position to the second position.

  Then, the flow of fuel from the first communication path 31 to the second communication path 32 is blocked, and the fuel in the back pressure chamber 22 is discharged to the low pressure fuel path 43. As a result, the pressure in the back pressure chamber 22 decreases, so that the force that presses the needle 16 against the injection hole side (valve closing force) lifts the needle 16 by the fuel pressure supplied to the high pressure chamber 21 toward the counter injection hole side. Since it is lower than the force (valve opening force) to be attempted, the seat portion 18 is separated from the valve seat 12, and the fuel in the high pressure chamber 21 is injected from the injection hole 13.

  Thereafter, when the energization to the piezo stack is stopped, the electric charge of the piezo stack is released, and when the piezo stack contracts, the force acting on the valve needle 55 via the driving force transmitting portion is released. For this reason, the valve body 45 is moved to the first position by the urging force of the spring 46 and the high pressure fuel pressure from the first communication path 31, and the high pressure fuel passes through the first and second communication paths 31 and 32. It is supplied to the back pressure chamber 22. As a result, since the pressure in the back pressure chamber 22 rises again, the seat portion 18 is seated on the valve seat 12 when the valve closing force exceeds the valve opening force, and fuel is injected from the injection hole 13. finish.

  Here, the plate 30 will be described in more detail. FIG. 2 shows a plan view of the body-side end face 34 of the plate 30, and FIG. 3 shows the plate-side end face 15 of the nozzle body 10. As shown in FIG. 2, when the plate-side end surface 15 of the nozzle body 10 is brought into contact with the body-side end surface 34 of the plate 30, the opening 35 b faces the annular passage 23. An annular groove 35 whose bottom 35a is connected to the third high-pressure fuel passage 33 and the first communication passage 31 is formed.

  If the annular groove 35 is formed in the plate 30 as described above, the needle receiving hole 11 is formed without forming a notch for supplying fuel from the high pressure fuel passage to the needle receiving hole 11 on the nozzle body side. Even if the inner diameter of the third high-pressure fuel passage 33 is not enlarged, a passage area for supplying fuel to the annular passage 23 formed in the needle accommodation hole 11 and thus to the high-pressure chamber 21 can be secured.

  As a result, since the thickness of the nozzle body 10 can be ensured, a decrease in pressure resistance performance of the nozzle body 10 can be suppressed.

  In addition, since the fuel injection valve 1 of the present embodiment has a structure that suppresses a decrease in pressure resistance performance, it is suitable for use in, for example, a fuel injection system having a system pressure of 180 MPa or more.

  If the passage area, that is, the area of the portion where the opening 35b of the annular groove 35 and the opening of the needle accommodation hole 11 overlap with each other, the third high pressure fuel passage 33 can be secured. The high-pressure fuel can be supplied to the annular passage 23 and the high-pressure chamber 21 without reducing the flow rate of the high-pressure fuel flowing through

  In the present embodiment, the annular groove 35 is formed in the plate 30 as a specific means for securing the passage area. However, according to the above concept, it is sufficient if the passage area can be secured, so the groove is annular. There is no need, and any groove having a certain width and circumferential length may be used. The reason why the groove is annular as in this embodiment is that the occurrence of burrs or the like when the groove is processed in the plate 30 can be reduced.

  The width of the annular groove 35 is preferably equal to or larger than the passage diameter of the third high-pressure fuel passage 33. According to this structure, since the generation | occurrence | production of a burr | flash etc. can be suppressed when the annular groove 35 is formed, a process becomes easy.

  The width and depth of the annular groove 35 is such that the sum of the circumferential sectional area of the annular passage 23 and the circumferential sectional area of the annular groove 35 is not less than 1/2 of the passage sectional area of the third high-pressure fuel passage 33. It is preferable that the width and the depth satisfy a certain condition. Furthermore, it is more preferable that the width of the annular groove 35 is equal to or larger than the passage diameter of the third high-pressure fuel passage 33.

  According to this, high-pressure fuel flowing through the third high-pressure fuel passage 33 can be spread all over the annular groove 35 and the annular passage 23, and a large amount of high-pressure fuel can be passed through the fourth high-pressure fuel passage 24. Can be supplied to the high-pressure chamber 21.

  The pin hole 37 formed in the plate 30, the valve plate 40, and the valve body 50 and the pin groove 14 formed in the nozzle body 10 engage the pin 60, so that the plate 30, the valve plate 40, the valve body 50, Although the circumferential position of the nozzle body 10 can be fixed, there is a dimensional tolerance between the pin hole 37 and the pin groove 14 and the pin 60. Then, the plate 30 and the nozzle body 10 may be displaced in the radial direction by the dimensional tolerance.

  On the other hand, in the present embodiment, even if the annular groove 35 is deviated from the dimensional tolerance, the opening 35 b is formed so as to be shifted in the radial direction from the pin groove 14 so as not to overlap the pin groove 14. According to this, the opening 35b of the annular groove 35 overlaps with the pin groove 14, and the pressure performance of the nozzle body 10 can be prevented from lowering due to the high pressure fuel entering the structurally weak pin groove 14.

  In addition, when the plate-side end surface 15 of the nozzle body 11 is brought into contact with the body-side end surface 34 of the plate 30, the outer peripheral wall 35 c of the annular groove 35 is formed on the outer peripheral side with respect to the inner wall of the needle housing hole 11. Yes.

  Also with this configuration, since the thickness of the nozzle body 10, particularly the thickness of the pin groove 14 portion, is increased, it is possible to suppress a decrease in pressure resistance of the nozzle body 10.

  A meat stealing portion 36 for increasing the surface pressure between the nozzle body 10 and the plate 30 is formed on the outer peripheral side of the annular groove 35. As shown in FIG. 2, the meat stealer 36 is provided with a leak passage 38 that leads to the low-pressure fuel passage 43.

  According to this configuration, even if the high-pressure fuel in the annular groove 35 flows between the body-side end face 34 and the plate-side end face 15 and flows out of the annular groove 35, the fuel is temporarily stored in the meat stealing portion 36. be able to. In the case of the present embodiment, the fuel stored in the meat stealer 36 can be returned to the fuel tank via the leak passage 38. As a result, fuel leakage to the outside of the fuel injection valve 1 can be prevented.

  Further, the meat stealing portion 36 is formed on the body side end surface 34 of the plate 30. That is, the meat stealing portion 36 is formed on the same end surface as the annular groove 35. According to this, even if the nozzle body 10 and the plate 30 are displaced in the radial direction due to the dimensional tolerance of the pin 60, the pin hole 37 or the pin groove 14, the distance between the outer peripheral wall 35c of the annular groove 35 and the meat stealing portion 36, That is, the seal length 39 does not change (see FIG. 2). For this reason, liquid-tightness is securable.

It is principal part sectional drawing of the fuel injection valve by one Embodiment of this invention. It is a top view of the body side end surface of the plate of the fuel injection valve of FIG. It is a top view of the plate side end surface of the nozzle body of the fuel injection valve of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Fuel injection valve, 10 Nozzle body, 11 Needle accommodation hole, 12 Valve seat, 13 Injection hole, 14 Pin groove, 15 Plate side end surface, 16 Needle, 17 Flange, 18 Seat part, 19 Cylinder, 19a Upper end surface, 19b Lower end surface , 19c outer peripheral wall, 19d inclined surface, 19e inner peripheral wall, 20 nozzle spring, 21 high pressure chamber, 22 back pressure chamber, 23 annular passage, 24 fourth high pressure fuel passage, 30 plate, 31 first communication passage, 32 second connection Passage, 33 third high pressure fuel passage (fuel passage), 34 body side end face, 35 annular groove, 35a bottom, 35b opening, 35c outer peripheral wall, 36 meat stealing portion, 37 pin hole, 38 leak passage, 39 seal length , 40 Valve plate, 41 Valve chamber, 42 Second high pressure fuel passage, 43 Low pressure fuel passage, 44 Valve needle housing Hole, 45 Valve body, 46 Spring, 50 Valve body, 51 Low pressure chamber, 52 First high pressure fuel passage, 53 First piston, 54 Second piston, 55 Valve needle, 56 Piston cylinder, 57 First piston spring, 58 First 2 piston spring, 59 oil tight chamber, 60 pins, 70 retaining nut

Claims (7)

A nozzle body having an injection hole for injecting fuel, and a needle accommodation hole for accommodating a needle for controlling injection from the injection hole;
A fuel injection valve provided adjacent to the nozzle body and having a plate having a fuel passage for supplying fuel to the needle accommodation hole,
An annular groove for connecting the fuel passage and the needle accommodation hole is formed on an end surface of the plate on the nozzle body side. The fuel injection valve according to claim 1, wherein
In the needle accommodation hole, a cylinder having a hollow portion in which the needle slides is provided adjacent to the plate,
The cylinder communicates with the needle passage hole, the annular passage communicating with the annular groove, and the nozzle hole at a boundary between the outer peripheral wall of the cylinder and the inner wall of the needle housing hole facing the cylinder. Divided into high pressure chambers,
The width and depth of the annular groove satisfy the condition that the sum of the circumferential cross-sectional area of the annular passage and the circumferential cross-sectional area of the annular groove is ½ or more of the passage cross-sectional area of the fuel passage. A fuel injection valve characterized by having such a width and depth. The fuel injection valve according to claim 1 or 2,
The nozzle body has a pin groove or a pin hole for locking a pin for determining a circumferential position between the nozzle body and the plate,
The fuel injection valve, wherein the pin groove or the pin hole and the annular groove are displaced in a radial direction. The fuel injection valve according to any one of claims 1 to 3,
The fuel injection valve according to claim 1, wherein a width of the annular groove is equal to or greater than a passage diameter of the fuel passage. In the fuel injection valve according to any one of claims 1 to 4,
A meat stealing portion is formed on the nozzle body side end surface of the plate,
The fuel injection valve, wherein the meat stealing portion and the annular groove are displaced in a radial direction. The fuel injection valve according to any one of claims 1 to 5,
The fuel injection valve according to claim 1, wherein an outer peripheral edge of the annular groove is located outside an inner wall of the needle accommodation hole. A nozzle body having an injection hole for injecting fuel, and a needle accommodation hole for accommodating a needle for controlling injection from the injection hole;
A fuel injection valve provided adjacent to the nozzle body and having a plate having a fuel passage for supplying fuel to the needle accommodation hole,
A groove portion that connects the fuel passage and the needle accommodation hole is formed on an end surface of the plate on the nozzle body side,
The groove is a groove having a width or a circumferential length in which an area of a portion where the needle accommodation hole and the opening of the groove overlap is equal to or larger than a passage sectional area of the fuel passage. .

Images